Banerjee, an associate professor of mechanical engineering, has developed a patented
technology that uses ultrasonic acoustic waves and sensors to diagnose the condition
of metal and composite materials in aerospace vehicles and concrete in structures
including bridges. Acoustic waves are transmitted through the material, and sensors
gather unique vibrational signatures that are analyzed to detect cracks or stress
points.

We want to ‘talk’ with this material using ultrasound acoustical waves. I want to
be able to determine if it’s going to fail even before any symptoms of unwellness
have appeared.

Sourav Banerjee, engineering

“With sensors, you can diagnose material breakdown long before it results in a catastrophic
failure,” Banerjee says. “The traditional approach of detecting a crack, then repairing
it, works for civil structures like bridges. But for aircraft structure we don’t have
that luxury of time. Once there is a crack, it’s already too late.”

Banerjee’s new quest is to further refine his ultrasonic wave technology to detect
material breakdown before it’s visible. He points to composite material now used in
many airplanes and spacecraft that appears undamaged even after sustaining a physical
blow. The material is perhaps degraded, like an invisible bruise, he says, and it
develops a “memory” of the stresses it has endured.

“I’m looking into a more physics-based understanding of these materials,” Banerjee
says. “We want to ‘talk’ with this material using ultrasound acoustical waves. I want
to be able to determine if it’s going to fail even before any symptoms of unwellness
have appeared.

“There’s no way to diagnose material memory so far, be we have found a unique feature
in the linear and nonlinear ultrasonic wave — we call it the coda or tail wave — that
can perhaps tell us what memory has been collecting in a material.”

Banerjee has worked on material health research with most of the world’s leading aircraft
manufacturers and is currently involved in a NASA-funded project that involves analyzing
materials that will be used for the next Mars mission.

On another front, Banerjee is exploring how to harvest energy from large structures
by tapping into their ever-present vibrations. Think of a busy bridge with traffic
rumbling across it, he says. “Why can’t we put some type of harvester in place with
smart materials to capture the energy and store it in a battery?” This isn’t an idle
dream: Bannerjee has already applied for a patent for the energy-harvesting plan.

Extending his acoustical energy research in a biomedical direction, Banerjee envisions
developing artificial ears that can sense sound in ranges below and above mere human
capability, a bio mimic that could make Banerjee the ultimate “whisperer” in sensor
technology.

Breakthrough Stars

Breakthrough awards, presented each year by the Office of the Vice President for Research, recognize faculty and graduate students for their research and scholarly excellence.
The Breakthrough Leadership in Research award recognizes the university’s distinguished
senior faculty; the Breakthrough Star award honors outstanding early career faculty;
and the Breakthrough Graduate Scholar award acclaims exceptional graduate students.
Learn more in Breakthrough publications.